It all started on 4chan's /vg/ board in its regular visual novel thread:
The twitter account has some vague cyber-y tweets related to loading and then the trailer linked in the 4chan post. The unlisted video has English subtitles so some effort was put into it, though the "summer 2018" part is probably not happening. Also is it just me or is the tl of the "you betrayed me?!" line weird based on the voice clip? Like she doesn't sound surprised. oops getting tangential here...
So what does it all mean? well, SteppenWolf is apparently a team within the baldr series or something, and TGL is a company which has Giga, makers of baldr, as an imprint. But of course anyone could have made the twitter account and the 4chan post and incorporated just the right references to make things interesting. All in all until we get something more official there's no way to tell if this is a hoax or not; I would recommend not getting too hyped.
Okay zaka but where's the realdeal silly speculation at?
Very well, dear rhetorical-questioner-kun. So like you know how Aroduc was fan translating baldr sky and then sekai project licensed it and then negotiations broke down and it was basically
typical sekai project a terrible fracas? The outside guess is that instead of actually quitting tl like he seemed to when he dropped off the scene he's been working on this. It even matches up with things I seem to remember him mentioning about baldr force being better but people wanting sky or something. Anyway take this with more salt than a room containing solidbatman, originalren, astro, steve, and itsangetime, but it's like, maybe possible. Maybe.
Y u no make forum thread?
I want to feel like a special snowflake. Also I figured this'd be a decent water-testing opportunity for this kind of content so here I go.
NEW INFO 17:00 swedish time 15/9:
Two new videos have been posted in /vn/ and on the twitter account: